LAB REPORT
EXERIMENT.NO. 4
Resolving Forces in Truss
STRUCTURAL MECHANICS 1
(CIVIL0006)
Submitted by: Fahad Ali AL-Amri 11f8247 Session B Submitted to: Dr. Ram Kishore Manchiryal
Fall2014
1. Experiment Name: Resolving Forces in Truss
2. Aim:
The force in the member of truss is to be compared with the forces measured in the members with the values found by resolution at the joints.
3. Scope of the experiment:
The experiment is to know the nature of force in each member of the Truss.
4. Experiment Setup
As shown in figure 1, check the joints in the truss and the loads.
Figure1: free body diagram of the frame
5. Apparatus:
HST 17 Structural frame
6. Methods of experiment:
1. Apply preload to the truss of say 30N to 50N to get the joints stabilized. Release this load two or three times in order to ensure setting of the joints and members.
2. On the last cycle keep the preload attached. It may be necessary to adjust this force from time to time as the truss settles.
3. Zero (tare) all connected channels of the HAD200. This will be the zero (NO LOAD) starting value. Record all stains for all channels in table1.
4. Apply loads to the truss via the loading mechanism in approximately 10 N increments up to a 100 N. At each load increment record the individual channel strain values in table1
7. Observations and calculations:
Table1: Member strains for Loading
Truss member No.
Applied Load, F(N)
Applied Force from HAD 200
0
9.8
19.7
31.0
41.4
55.1
59.1
69.4
79.6
89.8
99.4
U1L2(1)
Strain ()
0
1
2
3
3
13
20
53
64
69
109
Force(N)
0
6.25
12.5
18.75
18.75
81.25
125
331.25
400
431.25
681.25
Theoretical Force, N
0
11.51
23.15
36.43
48.65
64.75
69.45
81.56
93.54
105.53
116.81
L1L2(2)
Strain ()
0
3
3
2
44
0
-4
-33
-39
-39
-75
Force(N)
0
18.75
18.75
12.5
25
0
-25
-206.25
-243.75
-243.75
-468.75
Theoretical Force, N
0
6.05
12.16
19.13
25.55
34.01
36.48
42.84
49.14
55.43
References: 1. Dr. Kishore, R (20140 Resolving forces in truss. Structural Mechanics 1, Middle East College, 04th December 2014[lab manual taken by Joe, A] 2. Operating manual provided along with apparatus ES3.